where the FBI has been involved in the search for the missing flight. Good morning to you, Pierre. Reporter: Good morning, robin. The FBI is playing a lipped but possibly key role. They've been given a disk from the pilot's flight simulator seen behind my, some of the information on that was deleted and the FBI's job is to see if they can recover it. They want to know if the pilot played any role in the disappearance and the key is if he was practicing maneuvers like the plane made but sources say nothing is conclusive. They don't know if the pilot did anything wrong. My sources say it's critical to find that plane to get real answers. We know early on, terrorism was somewhat discounted. Are they still looking into ties to possibly being tied to terrorism? Reporter: They are still looking at everything so far. No information of ties to terrorism. Sources say that's the frustration. They just don't have a lot of answers. That's why finding that plane is so critical. But what does it say to you the FBI is becoming so involved? The primary reason the 3 Malaysians allowed them to play that role and gave them this disk and at least they can play a forensic role but not on the ground in Malaysia doing anything significant. All right, Pierre Thomas there in Washington, thanks so much.

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